Which of the following numbers can never be an outcome for the single roll of an unbiased die?
7
Sample space for a single roll of a die = S {1, 2, 3, 4, 5, 6}
⇒ The numbers on a dice are 1, 2, 3, 4, 5, and 6.
We can get any one of these numbers on a single roll of the die.
Hence, number 7 can never occur. It is an impossible event.